X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fvlib%2Fbuffer_funcs.h;h=f346676baee995690037f1e7b480442584f32f50;hb=f869028740aaebeb0375077d4d84fa07a17fff1a;hp=fd051de53de090c356323c55102c4a9e434ae099;hpb=bd69a5f24c6e83e9101f203dd124864fb2877a17;p=vpp.git

diff --git a/src/vlib/buffer_funcs.h b/src/vlib/buffer_funcs.h
index fd051de53de..f346676baee 100644
--- a/src/vlib/buffer_funcs.h
+++ b/src/vlib/buffer_funcs.h
@@ -489,7 +489,15 @@ vlib_buffer_copy (vlib_main_t * vm, vlib_buffer_t * b)
 
   vec_validate (new_buffers, n_buffers - 1);
   n_alloc = vlib_buffer_alloc (vm, new_buffers, n_buffers);
-  ASSERT (n_alloc == n_buffers);
+
+  /* No guarantee that we'll get all the buffers we asked for */
+  if (PREDICT_FALSE (n_alloc < n_buffers))
+    {
+      if (n_alloc > 0)
+	vlib_buffer_free (vm, new_buffers, n_alloc);
+      vec_free (new_buffers);
+      return 0;
+    }
 
   /* 1st segment */
   s = b;
@@ -518,9 +526,114 @@ vlib_buffer_copy (vlib_main_t * vm, vlib_buffer_t * b)
       d->flags = s->flags & flag_mask;
     }
 
+  vec_free (new_buffers);
   return fd;
 }
 
+/** \brief Create multiple clones of buffer and store them in the supplied array
+
+    @param vm - (vlib_main_t *) vlib main data structure pointer
+    @param src_buffer - (u32) source buffer index
+    @param buffers - (u32 * ) buffer index array
+    @param n_buffers - (u8) number of buffer clones requested
+    @param head_end_offset - (u16) offset relative to current position
+           where packet head ends
+    @return - (u8) number of buffers actually cloned, may be
+    less than the number requested or zero
+*/
+
+always_inline u8
+vlib_buffer_clone (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
+		   u8 n_buffers, u16 head_end_offset)
+{
+  u8 i;
+  vlib_buffer_t *s = vlib_get_buffer (vm, src_buffer);
+
+  ASSERT (s->n_add_refs == 0);
+  ASSERT (n_buffers);
+
+  if (s->current_length <= head_end_offset + CLIB_CACHE_LINE_BYTES * 2)
+    {
+      buffers[0] = src_buffer;
+      for (i = 1; i < n_buffers; i++)
+	{
+	  vlib_buffer_t *d;
+	  d = vlib_buffer_copy (vm, s);
+	  if (d == 0)
+	    return i;
+	  buffers[i] = vlib_get_buffer_index (vm, d);
+
+	}
+      return n_buffers;
+    }
+
+  n_buffers = vlib_buffer_alloc_from_free_list (vm, buffers, n_buffers,
+						s->free_list_index);
+  if (PREDICT_FALSE (n_buffers == 0))
+    {
+      buffers[0] = src_buffer;
+      return 1;
+    }
+
+  for (i = 0; i < n_buffers; i++)
+    {
+      vlib_buffer_t *d = vlib_get_buffer (vm, buffers[i]);
+      d->current_data = s->current_data;
+      d->current_length = head_end_offset;
+      d->free_list_index = s->free_list_index;
+      d->total_length_not_including_first_buffer =
+	s->total_length_not_including_first_buffer + s->current_length -
+	head_end_offset;
+      d->flags = s->flags | VLIB_BUFFER_NEXT_PRESENT;
+      d->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
+      clib_memcpy (d->opaque, s->opaque, sizeof (s->opaque));
+      clib_memcpy (vlib_buffer_get_current (d), vlib_buffer_get_current (s),
+		   head_end_offset);
+      d->next_buffer = src_buffer;
+    }
+  vlib_buffer_advance (s, head_end_offset);
+  s->n_add_refs = n_buffers - 1;
+  while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
+    {
+      s = vlib_get_buffer (vm, s->next_buffer);
+      s->n_add_refs = n_buffers - 1;
+    }
+
+  return n_buffers;
+}
+
+/** \brief Attach cloned tail to the buffer
+
+    @param vm - (vlib_main_t *) vlib main data structure pointer
+    @param head - (vlib_buffer_t *) head buffer
+    @param tail - (Vlib buffer_t *) tail buffer to clone and attach to head
+*/
+
+always_inline void
+vlib_buffer_attach_clone (vlib_main_t * vm, vlib_buffer_t * head,
+			  vlib_buffer_t * tail)
+{
+  ASSERT ((head->flags & VLIB_BUFFER_NEXT_PRESENT) == 0);
+  ASSERT (head->free_list_index == tail->free_list_index);
+
+  head->flags |= VLIB_BUFFER_NEXT_PRESENT;
+  head->flags &= ~VLIB_BUFFER_TOTAL_LENGTH_VALID;
+  head->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
+  head->flags |= (tail->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID);
+  head->next_buffer = vlib_get_buffer_index (vm, tail);
+  head->total_length_not_including_first_buffer = tail->current_length +
+    tail->total_length_not_including_first_buffer;
+
+next_segment:
+  __sync_add_and_fetch (&tail->n_add_refs, 1);
+
+  if (tail->flags & VLIB_BUFFER_NEXT_PRESENT)
+    {
+      tail = vlib_get_buffer (vm, tail->next_buffer);
+      goto next_segment;
+    }
+}
+
 /* Initializes the buffer as an empty packet with no chained buffers. */
 always_inline void
 vlib_buffer_chain_init (vlib_buffer_t * first)
@@ -679,14 +792,23 @@ vlib_buffer_init_for_free_list (vlib_buffer_t * dst,
   /* Make sure buffer template is sane. */
   ASSERT (fl->index == fl->buffer_init_template.free_list_index);
 
+  clib_memcpy (STRUCT_MARK_PTR (dst, template_start),
+	       STRUCT_MARK_PTR (src, template_start),
+	       STRUCT_OFFSET_OF (vlib_buffer_t, template_end) -
+	       STRUCT_OFFSET_OF (vlib_buffer_t, template_start));
+
+  /* Not in the first 16 octets. */
+  dst->n_add_refs = src->n_add_refs;
+
   /* Make sure it really worked. */
-#define _(f) dst->f = src->f
+#define _(f) ASSERT (dst->f == src->f);
   _(current_data);
   _(current_length);
   _(flags);
   _(free_list_index);
 #undef _
   ASSERT (dst->total_length_not_including_first_buffer == 0);
+  ASSERT (dst->n_add_refs == 0);
 }
 
 always_inline void
@@ -711,15 +833,32 @@ vlib_buffer_init_two_for_free_list (vlib_buffer_t * dst0,
   /* Make sure buffer template is sane. */
   ASSERT (fl->index == fl->buffer_init_template.free_list_index);
 
+  clib_memcpy (STRUCT_MARK_PTR (dst0, template_start),
+	       STRUCT_MARK_PTR (src, template_start),
+	       STRUCT_OFFSET_OF (vlib_buffer_t, template_end) -
+	       STRUCT_OFFSET_OF (vlib_buffer_t, template_start));
+
+  clib_memcpy (STRUCT_MARK_PTR (dst1, template_start),
+	       STRUCT_MARK_PTR (src, template_start),
+	       STRUCT_OFFSET_OF (vlib_buffer_t, template_end) -
+	       STRUCT_OFFSET_OF (vlib_buffer_t, template_start));
+
+  /* Not in the first 16 octets. */
+  dst0->n_add_refs = src->n_add_refs;
+  dst1->n_add_refs = src->n_add_refs;
+
   /* Make sure it really worked. */
-#define _(f) dst0->f = src->f;  dst1->f = src->f
+#define _(f) ASSERT (dst0->f == src->f);  ASSERT( dst1->f == src->f)
   _(current_data);
   _(current_length);
   _(flags);
   _(free_list_index);
 #undef _
+
   ASSERT (dst0->total_length_not_including_first_buffer == 0);
   ASSERT (dst1->total_length_not_including_first_buffer == 0);
+  ASSERT (dst0->n_add_refs == 0);
+  ASSERT (dst1->n_add_refs == 0);
 }
 
 #if CLIB_DEBUG > 0